The Italian company AnsaldoBreda, which manufactures the Muni trains, was recently awarded a five-year $54 million contract to overhaul the fleet's automatic doors and steps, as well as the air supply units and other electrical and mechanical components.
The company maintains a facility in Pittsburg where the upgrades will be done.
According to Muni, 143 of its 151 light-rail vehicles will be getting the upgrades, a few at a time over the next five years. SFMTA CEO Nathaniel Ford said the improvements would boost the reliability of the light-rail vehicles.
The contract was awarded using $9 million in federal stimulus funding, plus additional federal, local and infrastructure funding, according to Muni.